Treatment of certain diseases requires use of one or more different active medicaments. Optimum therapeutic doses of these different active medicaments may have to be delivered in a specific relationship with each other. A single formulation of these different active medicaments may not be possible for reasons such as stability, toxicology and ineffective therapeutic performance.
Delivery related problems of different active medicaments when delivering one or more active medicaments includes interaction with each other during the long-term, shelf life storage of the formulation. Hence the preferred method of delivery involves storing one or more active medicaments separately and combining them at the point of delivery by the various known delivery mechanisms such as inhalation route, pumps, needle-less injection and injection.
A further problem in the multi medicament combination therapy is that quantities and/or proportions of one or more active medicaments may vary for each user and also may vary at different stages of therapy. Other possible variations in the combination therapy of one or more active medicaments are variation in doses in response to a patient's symptoms or physical condition. Hence in such cases pre-mixed formulations of multiple active medicaments may prove to be ineffective as these pre-mixed formulations would have a fixed ratio of different active medicaments.
Use of more than one drug delivery device for delivery of one or more medicaments calls for additional patient skills such as dexterity, computational competency etc. Besides the economic factor other associated problems may be in terms of handling multi devices especially when the patient is on high mobility and storage of more than one drug delivery device.
Hence the need for delivery of one or more active medicaments may be accomplished by devices and methods by a single injection or delivery step that is simple for the user to perform.
Prior art patents U.S. Pat. Nos. 8,092,421, 8,092,422 and 8,376,987 related to delivery of one or more active medicaments comprise two chamber syringes or carpule. Though chamber syringes of these prior arts may be able to hold one or medicaments they are unsuitable for use with an injection pen device. U.S. Pat. No. 8,651,338 patent relates to a delivery device for delivery of predefined combination of one or more medicaments comprising a user settable variable dose and a fixed dose wherein the user may be able to set the variable doses of one of the medicaments and the medicament may be dispensed through a single activation single dispense interface. In the invention of US '338 the fixed dosage of the drug is automatically set based on the setting of the variable dose. US'338 invention allows varying quantity of one of both medicaments; however varying “fixed” dose medicament may be achieved by manufacturing a variety of “fixed dose” medicament containing packages with each variant containing a different volume and/or concentration of the “fixed dose” medicament. US'338 invention is disadvantageous as it requires carrying several packages of different volume and/or concentration of the “fixed dose” medicament to meet the variable dose delivery requirements of the “fixed dose”; similarly prior art patent applications US20130261556, US20130245561, WO2012085173 and US20130197447 have the features of US'338 with regard to delivery of predefined combination of one or more medicaments.
The prior art patent application US20130245604 delivery device comprises two chambers to deliver three or more medicaments by a single variable dose setting through a single interface by a single activation. In this device the dosage of second medicament is chosen from an electro-mechanical dose setting mechanism from a programmed stored therapeutic dose profiles; the stored therapeutic dose profiles may be a linear dose profile; a non-linear dose profile; a fixed ratio-fixed dose profile; a fixed dose-variable dose profile; a delayed fixed dose-variable dose profile; or a multi-level, a fixed dose variable dose profile. The delivery device of US'604 is disadvantageous as use of any one or more combination of second medicament stored therapeutic dose profile would not be as flexible as a variable dose profile matching the wide variety of patient profile populace.
WO2012107493 relates to a delivery device for delivery of user settable variable doses of first medicament and preset doses of second medicament through either a single dispense interface wherein activation of the second medicament delivery system locks out the first dose delivery mechanism preventing further dose setting and administration of the first medicament.
WO1994003392 is directed to a variable proportion dispenser, especially useful for dispensing different types of insulin in amounts and proportions selected by the user. Once the combined dosage is selected, both in amount and proportion, the same proportion combined dosage will be automatically delivered for each actuation cycle of the dispenser. However the device disclosed in WO '392 does not permit the user to adjust both the quantity and proportion of the two medicament components to be delivered by the dispenser at will, but allows doing so by modification/replacement of certain components of the device etc. This calls for additional skill requirement and training for the patient in effecting modification in the device. Hence the use of WO'392 device has a limited scope for meeting the diverse variable doses of one or more medicaments and would fall short of full flexibility as per the patient's requirement. Further disadvantage of this device is that when only one medicament i.e. one type of insulin to be delivered, the second medicament may be accidentally set.
The prior art patent applications US20120220949, US20120130346, US20120136334, US20120226238, US20120123346, US20120116349, US20130144262, US201302-18089, US20130226081, US20130226143, US20130245563, EP2514455, EP2514-457, EP2514450, EP2514459, WO2012072562, WO2012143434 and WO2012-143435 are related to medicated module attachable to a drug delivery device each of which signifies a specified medicated module feature. The medicament in these medicated modules would be analogous to fixed doses which are non user settable ones as in US'338.
Hence there is a greater need for providing drug delivery devices and methods for the delivery of two or more medicaments in varying quantities as per the patient's requirement in a single injection or delivery step that is easier for the user to perform. In specific embodiments, the present invention overcomes the problem by providing separate storage containers for two or more medicaments with individual user operable dose locking mechanisms which enable dose setting by individual dose setters in the unlocked condition and gets locked on completion of the dose delivery. The patient or the healthcare professional would find the use of the drug delivery device easy.
The problem addressed by the present invention is to provide a drug delivery device and a method of its use wherein it facilitates administration of (i) two or more medicaments in varying quantities as per the patient's dosage requirement and (ii) three or more medicaments where in two of medicaments may be in varying quantities and third medicament may be in fixed quantity as per the patient's dosage requirement.